Convertible extension and step ladder



Sept. 29, 1925.

J. L. WHITNEY CONVERTIBLE EXTENSION AND STEP LADDER 2 Sheets-Sheet 1 IFiled Dec. 6, 1924 Sept. 29,v 1925.-

J.' L. WHITNEY CONVERTIBLE EXTENSION AND STEP LADDER Filed Dec. 6, 19242 Sheets-Sheet 2 Zlwoentoz Patented Sept. 29, 1925.

UNITED STATES r 1,555,344 PATENT OFFICE.

JOHN L. WHITNEY, OF SAN PEDRO, CALIFORNIA, ASSIGNOR OF ONE-THIRD TO WIL-I HELMINA WETMORE AND OF ONE-THIRD TO FRANK L. E. WETMORE, BOTH OF SANPEDRO, CALIFORNIA.

CONVERTIBLE EXTENSION AND STEP LADDER.

Application filed December 6, 1924. Serial No. 754,371.

To all whom it may concern:

Be it known that I, JoHN L. WHITNEY, a citizen of the United States,residing at San Pedro, in the county of Los Angeles and State ofCalifornia, have invented certain new and useful Improvements inConvertible Extension and Step Ladders, of which the following is aspecification, reference being had to the accompanying drawmgs.

This invention relates to ladders, and particularly to step-ladders.

One of the objects of the invention is to provide a ladder which isconvertiblefrom a long ladder such as adapted tobe disposed against theside of a house to a relatively short step-ladder having legs.

A further object of this invention is to provide a ladder of thischaracter formed in a plurality of sections, each of these sectionsbeing adapted to be disposed one upon th other and operatively engagedwith each other to thereby form a long ladder or to be disposed so thatone of the sections constitutes the brace or support for the othersection after the manner of the legs of the step-ladder.

A still further object is to provide a device of this character whereinthe section which constitutes the legs of the step-ladder is locked tothe rung section when the sections are arranged to form a step-ladder.

Other objects have to do with the details of construction andarrangement of parts as will appear more fully hereinafter.

My invention is illustrated in the accompanying drawings, wherein Figure1 is a side elevation of an extension ladder constructed in accordancewith my invention;

Figure 2 is a front elevation of the same;

Figur 3 is a perspective view of one end of one of the ladder sections;

Figure 4 is a fragmentary side elevation of two of the ladder sectionsput together parallel to each other; 4

Figure 5 is a side elevation showing the two ladder sections in Figure4. turned into angular relation to each other;

Figure 6 is a front elevation of the arrangementshown in Figure 5.

Referring to these drawings, it will be seen that my improved ladderconsists of two sections A and B, each of these sections comprising thelongitudinally extending side rails 10 and the rungs 11- The rails andrungs may be connected in any suitable manner and I do not wish to belimited to this. The rung 12 at one end of each section is longer thanthe rungs 11 so that it projects beyond the side rails 10. All of theserungs are held to the side rails in any suitable manner, and preferablybolts 13 are disposed through the side rails adjacent the ends thereofso as to prevent these side rails from splitting. The side rails attheir extremities are longitudinally slotted, as at 14, the inner end ofeach slot being rounded so that the slots of the side rails of onesection will accommodate the rung of the other section and so that atthe same time the side rails of the first section will have its slotsengaged with th rung 12 of the next adjacent section in the main nershown in Figure 2. It will be seen in this figure that the upper end ofsection B is narrower than the lower end of section A so as to fitinside of the section A,

So far I have described a ladder which is made of sections which may beoperatively engaged with each other to double the length of the ladderor, in fact, to increase its length more than double by having three ormore sections adjusted in this manner, and I will now describe themanner in which the two sections of the ladder may be converted into astep-ladder. Mounted upon one rail of the section A adjacent the upperend thereof is an outwardly bowed meta] strap 15 which is held to therail by means of bolts 16 or by any other suitable means. The section Bis also provided witlr the metal strip 15 held on by bolts 16, the metalstrip being outwardly bowed at its middle. Under these circumstances,when the section A is disposed as shown in Figure 6 with the rails ofsection A laterally off-set with relation to the rails of section B,then it will be obvious that one end of the rung 12 of section A will bedisposed through the bowed strap 15 of section B, while one end of therung 12 of section B will be disposed through the bowed strap 15 ofsection A and that the two sections will thus be operatively pivoted orhingedto each other.

In order to lock the two sections together and prevent any lateralmovement of detachment, the rung 12 of section A is provided with aradially extending pin 17, as is the rung 12 of srction B, so that whenthe section B is turned into angular relation to the section A, thesepins or lugs will lock against the side edges of the strip and willprevent any lateral movement of the two sections so long as the twosections are in angular relation. At the same time, when the sectionsare turned into parallel relation by a lateral movement, the twosections may be readily separated. 7

It will also be seen from Figure 5 that when the two sections are turnedinto angular relation to form the step-ladder that the rails of thesection A will bear against the rung 12 of section B and the rails ofsection B in turn will. bear against the rung 12 of section A and thatthus the possible angular divergence of the two sections is limited.

Thus I have provided a ladder, one section of which may be used withoutany legs or supports, two sections of which may be used. without anylegs or supports to form an extension ladder, or in which one sectionmay be used as a support for the other section, and when the twosections are used in the form of a step-ladder with one section actingthe legs of the ladder and the other section as the main body of theladder, these two sections are locked together.

I do not wish to be limited to the detailed construction of the ladder,as it is obvious that this might be changed in many ways withoutdeparting from the spirit of the invention as defined in the appendedclaims.

I claim l. A ladder composed of two sections, the sections being adaptedto be fitted together to constitute an extension ladder, each of thesesections having upon one edge face an outwardly bowed bracket, each ofthese sections having adjacent one end a rung projecting laterallybeyond the rail of the section at one end of the rung and adapted toengage in the bracket of the other section whereby said sectionsare supported for swinging movement and may be placed in angular relation toeach other.

2. A convertible ladder comprising two sections so formed that they maybe disposed in conjunction with each other to provide an extensionladder, each section comprising parallel rails and rungs, each sectionhaving upon one edge face of one rail an outwardly bowed bracket andeach section havat one end a rung projecting laterally beyond a rail ofthe section and adapted to be inserted in the bracket of the section,the like rung of the other section constituting a stop limiting theangular movement of the sections.

3. A ladder composed of two sections, the

disposed across the bracket and in engagement over the outer edgethereof when the sections are in angular relation to each other tothereby lock the brackets from lateral movement.

In testimony whereof I hereunto ailix.

my signature.

JOHN L. 'WHITNEY

